Bug 59967 - Not Verifiable: Cannot take the address of a init-only field at 0x0002
Summary: Not Verifiable: Cannot take the address of a init-only field at 0x0002
Alias: None
Product: Runtime
Classification: Mono
Component: Verifier ()
Version: master
Hardware: PC Mac OS
: --- enhancement
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2017-10-04 16:51 UTC by Marek Safar
Modified: 2018-01-05 14:15 UTC (History)
4 users (show)

Tags: bugpool-archive
Is this bug a regression?: ---
Last known good build:

output (4.00 KB, application/x-msdownload)
2017-10-04 16:51 UTC, Marek Safar

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Description Marek Safar 2017-10-04 16:51:22 UTC
Created attachment 25105 [details]

This is a feature request from C# 7.2 Roslyn which has this new "optimization" which breaks peverify. They are aware of it but consider this to be peverify bug/limitation.

With following code

struct S
	public enum Type

	readonly Type type;

	public override string ToString ()
		return type.ToString ();

	public static void Main ()

attached .exe is generated with 2.6 csc and peverify fails with

Not Verifiable: Cannot take the address of a init-only field at 0x0002
Comment 1 Rodrigo Kumpera 2017-10-10 23:18:36 UTC
Is there a spec of that change? This sample is not enough to figure out what the new behavior is.
Comment 2 Marek Safar 2017-10-11 12:04:10 UTC
I am not really sure but I asked at https://github.com/dotnet/roslyn/issues/22485

I guess the easiest workaround would be to check for IsReadOnlyAttribute attribute on a struct and alter the checks based on that
Comment 3 Marek Safar 2017-11-21 22:07:03 UTC
This is hurting us on performace we need to run roslyn in legacy IL codegen for BCL builds